2009-02-22

Cutting down the drag !

Cheers !

Talking to an aviation enthusiast he said it is insane trying to make a record braker as a first project ! I realize this, but I see it comes as a by product.

I was calculating following:

Gear induced drag at 100 km/h is 10.1 kg ( cut down 4 kilos by reducing the size ).

Airframe drag at 219 mph ( new FAI 300 kg class record speed ) would be 92 lbs ( 41 kg ).

To reach this I figured I need 50 hp depending of the prop.

Ok after really hard study I got following specs that also match the drag measures that I got:



This also matches closely to figures VmaxProbe had ( and AR-5 )...cutting down the wing by 1 meter MAX III would be able to reach 240 mph at 50 hp. I added 10 % thrust to figure due to the fact that prop also has lift force..I have seen the thrust calculator does not recognize it.

What is really fantastic is that my almost beyond belief guesses of the economy seem to come true and indeed I could go 165 mph at 65% with 22 hp engine..and go way under 3 liter consumption a 100 km ( with APT possibly with just a liter !!!? ).

Aspect Ratio is 10 now...this will also lessen the drag. Max has also a wingloading same as in ballast filled open class sail plane has.



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